Click on the Tiling option in the Architecture ribbon. Once in the Tiling Sketcher mode, either select the Pick tool and select the room on which to apply the tiling, or manually sketch the outline of the tiling surface. Once finished, click on Apply to save changes.

Click on the targeted tiling. Then, either press the Delete key, or click on the Tiling drop-down menu in the left panel and select the Delete Tiling option.